Brush seal assembly

Abstract

A brush seal assembly includes a brush seal, a brush support portion, and an assembly support portion. The brush seal, which has a multitude of bristles forming an angle with respect to a radial direction of a rotating body rotated inside a casing, is disposed around an outer circumferential surface of the rotating body and is oriented with respect to the body's rotating direction. The brush support portion supports the brush seal by extending toward the rotating body while contacting a low-pressure side of the brush seal. The assembly support portion supports the brush seal and the brush support portion and to receive respectively a base end of the brush seal and an axial protrusion of the brush support portion. The brush support portion contacts the brush seal along a predetermined length, which is greater than that of a line following a bristle of the brush seal.

What is claimed is: 
     
       1. A brush seal assembly, comprising:
 a brush seal disposed around an outer circumferential surface of a rotating body rotated inside a casing and oriented with respect to a rotating direction of the rotating body, the brush seal having a multitude of bristles forming an angle with respect to a radial direction of the rotating body; 
 a brush support portion configured to support the brush seal by extending toward the rotating body while contacting a low-pressure side of the brush seal; and 
 an assembly support portion configured to support the brush seal and the brush support portion and to receive respectively a base end of the brush seal and an axial protrusion of the brush support portion, 
 wherein the assembly support portion includes: 
 a first support including a first inclined surface configured to contact and receive the third support, a brush base contacting edge, extending from the first inclined surface, configured to contact the base end of the brush seal and establish a first fluid space on a high-pressure side of the brush seal, and a first fluid space surface extending from the brush base contacting edge toward the rotating body; 
 a second support configured to support the brush support portion from a rear side of the brush support portion opposite to the contact with the brush seal; and 
 a third support disposed between the first and second supports to jointly support the brush seal and the brush support portion. 
 
     
     
       2. The brush seal assembly of  claim 1 , wherein the first support has a front surface provided with a first fluid guide arranged toward the rotating body to guide a high-pressure fluid to a point of contact between the brush seal and the rotating body. 
     
     
       3. The brush seal assembly of  claim 1 , wherein the second support includes:
 a second inclined surface configured to contact and receive the third support; 
 a vertical edge extending from the second inclined surface toward the brush support portion; 
 a protrusion groove formed adjacent to the vertical edge and configured to receive the axial protrusion of the brush support portion; and 
 a second fluid space surface, extending from the protrusion groove to the rotating body, configured to face the brush support portion and establish a second fluid space on a low-pressure side of the brush support portion. 
 
     
     
       4. The brush seal assembly of  claim 3 , wherein the second support further includes:
 a second fluid guide provided to a rear surface of the second support and arranged toward the rotating body to induce fluid passing through the brush support portion to pass the second support along a shortest path in the axial direction; and 
 an extending portion extending from the second fluid guide by a predetermined distance in the axial direction, the predetermined distance being greater than a depth of the protrusion groove. 
 
     
     
       5. The brush seal assembly of  claim 3 , wherein the protrusion groove is formed in the axial direction of the rotating body to receive the axial protrusion of the brush support portion, and wherein the axial protrusion is inserted into the protrusion groove. 
     
     
       6. The brush seal assembly of  claim 1 , wherein the third support includes:
 a third inclined surface corresponding to a contact surface of the first support; 
 a brush base groove configured to receive the brush base, the brush base groove extending from the third inclined surface and having a depth corresponding to a vertical height of a surface of the first support contacting the brush base; and 
 a brush support contacting surface, extending from the brush base groove in an axial direction of the rotating body, configured to receive and contact the brush support portion across at least two thirds of an overall width of the brush support portion in the axial direction. 
 
     
     
       7. The brush seal assembly of  claim 6 , wherein the third support further includes a lateral side corresponding to contacting surfaces of the second support, the lateral side comprising:
 a fourth inclined surface; and 
 a vertical surface extending from the fourth inclined surface to the brush support contacting surface. 
 
     
     
       8. The brush seal assembly of  claim 1 , wherein a first fluid space is formed between the brush seal and the first support facing the brush seal, and
 wherein the brush support portion comprises a plurality of inclined plates respectively extending toward the rotating body, and a second fluid space is formed between the brush support portion and the second support facing the brush support portion. 
 
     
     
       9. The brush seal assembly of  claim 1 , wherein the bristles of the brush seal are substantially inclined at a first inclination angle α 1  from perpendicular to the radial direction, the brush support portion is inclined at a second inclination angle α 2  from perpendicular to the radial direction, and the second inclination angle α 2  is greater than the first inclination angle α 1 , and
 wherein the brush seal maintains contact with the outer circumferential surface of the rotating body, and the brush support portion is spaced apart from the outer circumferential surface of the rotating body. 
 
     
     
       10. A brush seal assembly, comprising:
 a brush seal disposed around an outer circumferential surface of a rotor rotated inside a casing of a turbine and oriented with respect to a rotating direction of the rotor, the brush seal having a multitude of bristles forming an angle with respect to a radial direction of the rotor; 
 a brush support portion configured to support the brush seal by contacting a low-pressure side of the brush seal along a predetermined length extending toward the rotor; and 
 an assembly support portion configured to support the brush seal and the brush support portion, 
 wherein the predetermine length of the brush support portion is greater than that of a line following a bristle of the brush seal, and 
 wherein the assembly support portion includes: 
 a first support including a first inclined surface configured to contact and receive the third support, a brush base contacting edge, extending from the first inclined surface, configured to contact the base end of the brush seal and establish a first fluid space on a high-pressure side of the brush seal, and a first fluid space surface extending from the brush base contacting edge toward the rotating body; 
 a second support configured to support the brush support portion from a rear side of the brush support portion opposite to the contact with the brush seal; and 
 a third support disposed between the first and second supports to jointly support the brush seal and the brush support portion. 
 
     
     
       11. The brush seal assembly of  claim 10 , wherein a first fluid space is formed between the brush seal and a first surface of the assembly support portion facing the brush seal, and a second fluid space is formed between the brush support portion and a second surface of the assembly support portion facing the brush support portion. 
     
     
       12. The brush seal assembly of  claim 10 , wherein the brush support portion comprises a plurality of inclined plates of the predetermined length extending toward the rotating body. 
     
     
       13. The brush seal assembly of  claim 12 , wherein the bristles of the brush seal are substantially inclined at a first inclination angle α 1  from perpendicular to the radial direction, the inclined plates of the brush support portion are respectively inclined at a second inclination angle α 2  from perpendicular to the radial direction, and the second inclination angle α 2  is greater than the first inclination angle α 1 . 
     
     
       14. The brush seal assembly of  claim 10 , wherein the brush support portion is made of a material having a different thermal expansion rate in the radial direction of the rotor. 
     
     
       15. The brush seal assembly of  claim 10 , wherein the brush support portion has a different thickness in the radial direction of the rotor. 
     
     
       16. The brush seal assembly of  claim 10 , wherein the brush support portion has a thickness which is smaller, from the casing toward the rotor. 
     
     
       17. The brush seal assembly of  claim 10 , wherein the brush support portion includes:
 a first brush support extending from the assembly support portion toward the rotor, the first brush support having a first length and a first thermal expansion rate; and 
 a second brush support extending from the first brush support toward the rotor, the second brush support having a second length and a second thermal expansion rate less than the first thermal expansion rate. 
 
     
     
       18. The brush seal assembly of  claim 10 , wherein the assembly support portion is configured to receive respectively a base end of the brush seal and an axial protrusion of the brush support portion.